Ceramic tile is an excellent floor covering. It is very durable and generally easy to clean. However, ceramic tile is also extremely brittle. Therefore, when it is positioned on a floor it must have a subsurface that does not flex. This can be, for example, a concrete surface or a cementitious underlayment such as Wonderboard. Materials such as wood, including plywood and particle board are generally unacceptable.
Obviously, cement cannot be used in all applications. The cementitious board is heavy and difficult to cut.